How to create a tab with buttons? (Addin, C#)

I created a class, but it doesn't display the tab.

using System;

using System.Collections.Generic;
using System.Linq;
using System.Text;


///
// using Mindjet.MindManager.Interop;
using MM = Mindjet.MindManager.Interop;
using System.Windows.Forms;

namespace AddinTempl_3403.Core.RibbonTab2
{
class RibbonTab2
{
// Application === === === === === === === === === === === === === === === === === === === === === === === === === ===
MM.Application m_MindManager;

private static string DemoName = "Demo";

// AppRibbonTab === === === === === === === === === === === === === === === === === === === === === === === === === ===
MM.ribbonTab AppRibbonTab;
private readonly string TabCaption = DemoName + "Tab" + "/n" + "X"; // Alt + X - ??? ????? ??? ???????
private readonly string TabURI = "http://www.mindmanager.com/api/documentation/demos/ribbontab";

// AppRibbonGroup === === === === === === === === === === === === === === === === === === === === === === === === === ===
MM.RibbonGroup AppRibbonGroup;
private readonly string GroupCaption = DemoName + "Group" + "/n" + "X"; // '??? ?????? ??? ?????
private readonly string groupURI = "http://www.mindmanager.com/api/documentation/demos/ribbongroup";

// Control1 === === === === === === === === === === === === === === === === === === === === === === === === === ===
MM.Control Control1;

// command1 === === === === === === === === === === === === === === === === === === === === === === === === === ===
MM.Command command1;
private readonly static string CommandCaption = DemoName + "Cmd" + "/n" + "C"; // 'C - ??? ????? ???????
private readonly string CommandToolTip = "Create a new document" + "/n" + CommandCaption;


private readonly string ImagePath = $"{Environment.CurrentDirectory}" + @"\media\img\0000.jpg";
private readonly string AddInName = "Create a new document";

// private readonly string PATH = $"{Environment.CurrentDirectory}\\todoDataList.json";
// z:\vs\csharp\prb\3403\01_pr\01\Project\AddinTempl_3403\AddinTempl_3403\media\img\0000.jpg


public RibbonTab2(object application, string AddInName)
{
m_MindManager = application as MM.Application;

AppRibbonTab = m_MindManager.Ribbon.Tabs.Add(0, TabCaption, TabURI); // ???????? ??????? ?? ????? (' add a tab to the ribbon)
AppRibbonGroup = AppRibbonTab.Groups.Add(0, GroupCaption, groupURI, ImagePath); // ???????? ?????? ?? ??????? (' add a group to the tab)

command1 = m_MindManager.Commands.Add(AddInName, "DemoName");
command1.Caption = CommandCaption;
command1.ToolTip = CommandToolTip;


command1.SetDynamicMenu(Mindjet.MindManager.Interop.MmDynamicMenu.mmDynamicMenuTools, true);
//btn_1.UpdateState += new Mindjet.MindManager.Interop.ICommandEvents_UpdateStateEventHandler(mmCommand_UpdateState);
//btn_1.Click += new Mindjet.MindManager.Interop.ICommandEvents_ClickEventHandler(mmCommand_Click);


// command1.UpdateState += new Mindjet.MindManager.Interop.ICommandEvents_UpdateStateEventHandler(btn_1_UpdateState);
//command1.Click += new Mindjet.MindManager.Interop.ICommandEvents_ClickEventHandler(btn_1_Click);
command1.UpdateState += Command1_UpdateState;
command1.Click += Command1_Click;

Control1 = AppRibbonGroup.GroupControls.AddButton(command1);
// Control1.Caption = "Control1";
}

private void Command1_UpdateState(ref bool pEnabled, ref bool pChecked)
{
// throw new NotImplementedException();
}

private void Command1_Click()
{
MessageBox.Show(" Command1_Click ");
// throw new NotImplementedException();
}
}
}